@@ -558,6 +558,13 @@ static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,

     int pad_idx = in->pad_idx;

     int ret;

+    if (!ist->framerate.num) {

+        AVRational codec_fr = av_inv_q(ist->st->codec->time_base);

+        codec_fr.den *= ist->st->codec->ticks_per_frame;

+        if(av_q2d(codec_fr) < av_q2d(fr)*0.7)

+            fr = codec_fr;

+    }

+

     if (ist->st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {

         ret = sub2video_prepare(ist);

         if (ret < 0)